1. Field of the Invention
This invention relates to a split-phase starter for an electric motor.
2. Description of the Related Art
A conventional split-phase starter for an electric motor is constructed as disclosed, for instance, by Examined Japanese Utility Model Publication No. Sho-61-11985/(1986). The conventional split-phase starter is shown in FIG. 12. The main winding 50 of the electric motor is connected in series to coil 52 of a starting relay 51, and auxiliary winding 53 of the electric motor is connected in series with a capacitor 54. The capacitor 54 is shunted by a series circuit with a positive characteristic thermistor 55, having a positive temperature coefficient, and a normally open relay contact 56 of the starting relay 51.
In the case of the starter thus constructed, after the motor is started, the normally open relay contact 56 of the starting relay 51 is released to prevent the flow of current in the thermistor 55 thereby to minimize a loss of power attributing to the thermistor 55 during operation.
In the conventional split-phase starter shown in FIG. 12, the connection of the starting relay 51 and the positive temperature coefficient thermistor 55 is shown; however, the structure of the starting relay 51 and the thermistor 55 is not revealed. Nevertheless, in the conventional split-phase starter, the thermistor is held by a spring contact which is in contact with the inner wall of a casing, and therefore it is rather difficult to insert the thermistor in the casing, and the thermistor may be scratched while inserting. (Referring with Examined Japanese Utility Model Publication No. Sho-58-34722/(1983)).